Mechanism Of Drug Absorption

The procedure of development of unaltered medication from the site of organization to foundational dissemination.

1. Topic :- Mechanism Of Drug Absorption Presented By Tuhin Samanta B.Pharm

2. INTRODUCTION Pharmacokinetics and pharmacodynamics helps to maintain the products effective measurement of any kind of formulation by invitro and invivo test. ADME is the main function process after administration of a doses from and this process can be were defined by pharmacodynamics and pharmacokinetics.

3. Pharmacokinetics Pharmacokinetics means what the body dose to the drug. it is mainly concerned with absorption, Distribution, metabolism and excretion of the drug. A . Absorption :- Absorption can be defined as the process of movement of unchanged drug from the site of administration into systemic circulation. Mechanism Of Drug Absorption :- Parive diffusion :- Also called non-ionic diffusion. 90% of drugs absorbed by passive diffusion process. No carrier is required. No energy is required.

4. 2) Pore transport :- Also called connective transport, bulk flow, filtration . Here passage of the drugs occur through the aqueous pores present in the membrane. The driving force is the osmotic pressure difference across the membrane. This process important for Absorption of low molecular weight and low molecular size and water soluble drugs. E.g.- water, glucose etc. Ion pair transport :- Drugs like quaternary ammonium compounds, sulphonic drugs, which are ionized at all pH vales are absorbed ley ion pair transport. Due to ionization, these drugs having very low lipophilicits-test they penetrate the membrane by forming revisable neutral complexes with endogenous ions of the GIT like mucin such Neutral complexes have required lipophilicity for passive diffusion.

5. 4) Carrier Mediated Transport System Facilitated Diffusion B . Active transport A . Facilitated Diffusion :- Carrier mediated transport system. Passage of the drug molecule occurs from higher concentration to lower concentration. Driving force is the concentration gradient error the membrane. No energy is required.

6. B) Active Transport This transport mechanism requires energy in the form of ATP. Active transport process subdivided into:- Primary active transport :- ATP required directly. This process transfer only one ion or molecule in one direction. So it is uuiporter . E.g . Absorption of glucose. Carrier proteins involved in primary active transport are mainly two types: I ) Ion transporter II ) ABC transporter I ) Ion transporters :- Responsible for transporting ions in or out of the cell. Two types of ion transporter are present which responsible for intestinal. Absorption of drugs:- Organic anion transporter :- helps in absorption pravastatin , Atorvastatin . Organic cat ion transporter:- helps in Absorption of diphenydramine .

7. II) ABC transport:- Responsible for transporting small foreign molecules specially out of cells. So these pumps are called efflux pump. Example of ABC transporter is P- glycoprotein . It responsible for pumping hydrophobic drugs out of the cells. Presence of these types of transporter molecule in cells makes the cell resistant to variety of anti cancer drugs. That’s why P - glycoprotein called multi-drug resistant (MDR) protein. b) Secondary Active Transport :- No direct requirement of ATP The energy required in the transporting an ion aids transport of another ion or molecule either in the same direction or in the opposite direction.

8. Endocytosis Minor transport mechanism which involves engulfing extracellular materials with in a segment of the cell membrane to form a vesicle which is then pricked off intracellular . This phenomenon is responsible for absorption of fat starch, oil soluble vitamin like A,D,E,K and water soluble vitamin like Vit B 12, Drugs like insulin. Endocytosis Phagocytosis Pirocytosis Adsorptive uptake uptake of fluid solute. Of solid materials. Orally administered Sabine polio vaccine, botulihicim toxin are observed by

9. Conclusion The drug absorbent is the main function of ADME if the absorption process are as per the standard pharmacokinetics norms then activity by the product will be better.

10. Reference Abdou, H.M.: Dissolution, Bioavailability and Bioequivalence , Pennsylvania, Mack Publishing Company, 1989. Bankar, U.V.: Pharmaceutical Dissolution Testing , New York, Marcel Dekker, Inc., 1992. Florence, A.T and Attwood, D.: Physicochemical Principles Of Pharmacy , London, Macmillan, 1981.